[PATCH v4 3/3] spi: dt-bindings: nuvoton,npcm750-fiu: Convert to DT schema

[Tomer Maimon <tmaimon77@gmail.com>]

Convert the Nuvoton NPCM FIU binding to DT schema format.

Document the required control registers and the optional direct-
mapped flash window separately, matching the driver behavior
when the direct mapping is not described.

Signed-off-by: Tomer Maimon <tmaimon77@gmail.com>
---
 .../bindings/spi/nuvoton,npcm-fiu.txt         | 58 ------------
 .../bindings/spi/nuvoton,npcm750-fiu.yaml     | 93 +++++++++++++++++++
 2 files changed, 93 insertions(+), 58 deletions(-)
 delete mode 100644 Documentation/devicetree/bindings/spi/nuvoton,npcm-fiu.txt
 create mode 100644 Documentation/devicetree/bindings/spi/nuvoton,npcm750-fiu.yaml

diff --git a/Documentation/devicetree/bindings/spi/nuvoton,npcm-fiu.txt b/Documentation/devicetree/bindings/spi/nuvoton,npcm-fiu.txt
deleted file mode 100644
index fb38e96d395f..000000000000
--- a/Documentation/devicetree/bindings/spi/nuvoton,npcm-fiu.txt
+++ /dev/null
@@ -1,58 +0,0 @@
-* Nuvoton FLASH Interface Unit (FIU) SPI Controller
-
-NPCM FIU supports single, dual and quad communication interface.
-
-The NPCM7XX supports three FIU modules,
-FIU0 and FIUx supports two chip selects,
-FIU3 support four chip select.
-
-The NPCM8XX supports four FIU modules,
-FIU0 and FIUx supports two chip selects,
-FIU1 and FIU3 supports four chip selects.
-
-Required properties:
-  - compatible : "nuvoton,npcm750-fiu" for Poleg NPCM7XX BMC
-			     "nuvoton,npcm845-fiu" for Arbel NPCM8XX BMC
-  - #address-cells : should be 1.
-  - #size-cells : should be 0.
-  - reg : the first contains the register location and length,
-          the second contains the memory mapping address and length
-  - reg-names: Should contain the reg names "control" and "memory"
-  - clocks : phandle of FIU reference clock.
-
-Required properties in case the pins can be muxed:
-  - pinctrl-names : a pinctrl state named "default" must be defined.
-  - pinctrl-0 : phandle referencing pin configuration of the device.
-
-Optional property:
-  - nuvoton,spix-mode: enable spix-mode for an expansion bus to an ASIC or CPLD.
-
-Aliases:
-- All the FIU controller nodes should be represented in the aliases node using
-  the following format 'fiu{n}' where n is a unique number for the alias.
-  In the NPCM7XX BMC:
-  		fiu0 represent fiu 0 controller
-  		fiu1 represent fiu 3 controller
-  		fiu2 represent fiu x controller
-
-  In the NPCM8XX BMC:
-  		fiu0 represent fiu 0 controller
-  		fiu1 represent fiu 1 controller
-  		fiu2 represent fiu 3 controller
-  		fiu3 represent fiu x controller
-
-Example:
-fiu3: spi@c00000000 {
-	compatible = "nuvoton,npcm750-fiu";
-	#address-cells = <1>;
-	#size-cells = <0>;
-	reg = <0xfb000000 0x1000>, <0x80000000 0x10000000>;
-	reg-names = "control", "memory";
-	clocks = <&clk NPCM7XX_CLK_AHB>;
-	pinctrl-names = "default";
-	pinctrl-0 = <&spi3_pins>;
-	flash@0 {
-			...
-	};
-};
-
diff --git a/Documentation/devicetree/bindings/spi/nuvoton,npcm750-fiu.yaml b/Documentation/devicetree/bindings/spi/nuvoton,npcm750-fiu.yaml
new file mode 100644
index 000000000000..965904a98785
--- /dev/null
+++ b/Documentation/devicetree/bindings/spi/nuvoton,npcm750-fiu.yaml
@@ -0,0 +1,93 @@
+# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/spi/nuvoton,npcm750-fiu.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Nuvoton NPCM Flash Interface Unit (FIU) SPI Controller
+
+maintainers:
+  - Tomer Maimon <tmaimon77@gmail.com>
+
+allOf:
+  - $ref: /schemas/spi/spi-controller.yaml#
+
+description: |
+  NPCM FIU supports single, dual and quad communication interface.
+
+  The NPCM7XX supports three FIU modules:
+    FIU0 and FIUx support two chip selects
+    FIU3 supports four chip selects.
+
+  The NPCM8XX supports four FIU modules:
+    FIU0 and FIUx support two chip selects
+    FIU1 and FIU3 support four chip selects.
+
+  The FIU control register block is always required. The direct-mapped
+  flash window is optional because the controller can still access flash
+  through the UMA path when that mapping is not described.
+
+  Alias convention:
+    The '/aliases' node should define:
+      For NPCM7xx:  fiu0=&fiu0; fiu1=&fiu3; fiu2=&fiux;
+      For NPCM8xx:  fiu0=&fiu0; fiu1=&fiu3; fiu2=&fiux; fiu3=&fiu1;
+
+properties:
+  compatible:
+    enum:
+      - nuvoton,npcm750-fiu # Poleg NPCM7XX
+      - nuvoton,npcm845-fiu # Arbel NPCM8XX
+
+  reg:
+    description:
+      The first resource is the FIU control register block. An optional second
+      resource describes the direct-mapped flash window used for direct
+      read/write accesses.
+    minItems: 1
+    items:
+      - description: FIU control registers
+      - description: Memory-mapped flash contents
+
+  reg-names:
+    description:
+      Resource names for the control registers and optional direct-mapped
+      flash window.
+    minItems: 1
+    items:
+      - const: control
+      - const: memory
+
+  clocks:
+    maxItems: 1
+    description: FIU reference clock.
+
+  nuvoton,spix-mode:
+    type: boolean
+    description: Enable SPIX mode for an expansion bus to an ASIC or CPLD.
+
+required:
+  - compatible
+  - reg
+  - reg-names
+  - clocks
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/nuvoton,npcm7xx-clock.h>
+    spi@fb000000 {
+        compatible = "nuvoton,npcm750-fiu";
+        reg = <0xfb000000 0x1000>, <0x80000000 0x10000000>;
+        reg-names = "control", "memory";
+        #address-cells = <1>;
+        #size-cells = <0>;
+        clocks = <&clk NPCM7XX_CLK_SPI0>;
+
+        flash@0 {
+            compatible = "jedec,spi-nor";
+            reg = <0>;
+            #address-cells = <1>;
+            #size-cells = <1>;
+        };
+    };
-- 
2.34.1